/*
 * Copyright 2017 ~ 2025 the original author or authors. James Wong <jameswong1376@gmail.com>>
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.wl4g.infra.common.remoting;

import java.lang.reflect.Type;
import java.net.URI;
import java.nio.charset.Charset;
import java.util.Arrays;

import com.wl4g.infra.common.collection.multimap.MultiValueMap;
import com.wl4g.infra.common.lang.ObjectUtils2;
import com.wl4g.infra.common.remoting.standard.HttpHeaders;
import com.wl4g.infra.common.remoting.standard.HttpMediaType;

import io.netty.handler.codec.http.HttpMethod;

/**
 * Extension of {@link HttpEntity} that adds a {@linkplain HttpMethod method}
 * and {@linkplain URI uri}. Used in {@code RestTemplate} and
 * {@code @Controller} methods.
 * 
 * @see #getMethod()
 * @see #getUrl()
 */
public class HttpRequestEntity<T> extends HttpEntity<T> {

    private final HttpMethod method;
    private final URI url;
    private final Type type;

    /**
     * Constructor with method and URL but without body nor headers.
     * 
     * @param method
     *            the method
     * @param url
     *            the URL
     */
    public HttpRequestEntity(HttpMethod method, URI url) {
        this(null, null, method, url);
    }

    /**
     * Constructor with method, URL and body but without headers.
     * 
     * @param body
     *            the body
     * @param method
     *            the method
     * @param url
     *            the URL
     */
    public HttpRequestEntity(T body, HttpMethod method, URI url) {
        this(body, null, method, url, null);
    }

    /**
     * Constructor with method, URL, body and type but without headers.
     * 
     * @param body
     *            the body
     * @param method
     *            the method
     * @param url
     *            the URL
     * @param type
     *            the type used for generic type resolution
     * @since 4.3
     */
    public HttpRequestEntity(T body, HttpMethod method, URI url, Type type) {
        this(body, null, method, url, type);
    }

    /**
     * Constructor with method, URL and headers but without body.
     * 
     * @param headers
     *            the headers
     * @param method
     *            the method
     * @param url
     *            the URL
     */
    public HttpRequestEntity(MultiValueMap<String, String> headers, HttpMethod method, URI url) {
        this(null, headers, method, url, null);
    }

    /**
     * Constructor with method, URL, headers and body.
     * 
     * @param body
     *            the body
     * @param headers
     *            the headers
     * @param method
     *            the method
     * @param url
     *            the URL
     */
    public HttpRequestEntity(T body, MultiValueMap<String, String> headers, HttpMethod method, URI url) {
        this(body, headers, method, url, null);
    }

    /**
     * Constructor with method, URL, headers, body and type.
     * 
     * @param body
     *            the body
     * @param headers
     *            the headers
     * @param method
     *            the method
     * @param url
     *            the URL
     * @param type
     *            the type used for generic type resolution
     * @since 4.3
     */
    public HttpRequestEntity(T body, MultiValueMap<String, String> headers, HttpMethod method, URI url, Type type) {
        super(body, headers);
        this.method = method;
        this.url = url;
        this.type = type;
    }

    /**
     * Return the HTTP method of the request.
     * 
     * @return the HTTP method as an {@code HttpMethod} enum value
     */
    public HttpMethod getMethod() {
        return this.method;
    }

    /**
     * Return the URL of the request.
     * 
     * @return the URL as a {@code URI}
     */
    public URI getUrl() {
        return this.url;
    }

    /**
     * Return the type of the request's body.
     * 
     * @return the request's body type, or {@code null} if not known
     * @since 4.3
     */
    public Type getType() {
        if (this.type == null) {
            T body = getBody();
            if (body != null) {
                return body.getClass();
            }
        }
        return this.type;
    }

    @Override
    public boolean equals(Object other) {
        if (this == other) {
            return true;
        }
        if (!super.equals(other)) {
            return false;
        }
        HttpRequestEntity<?> otherEntity = (HttpRequestEntity<?>) other;
        return (ObjectUtils2.nullSafeEquals(getMethod(), otherEntity.getMethod())
                && ObjectUtils2.nullSafeEquals(getUrl(), otherEntity.getUrl()));
    }

    @Override
    public int hashCode() {
        int hashCode = super.hashCode();
        hashCode = 29 * hashCode + ObjectUtils2.nullSafeHashCode(this.method);
        hashCode = 29 * hashCode + ObjectUtils2.nullSafeHashCode(this.url);
        return hashCode;
    }

    @Override
    public String toString() {
        StringBuilder builder = new StringBuilder("<");
        builder.append(getMethod());
        builder.append(' ');
        builder.append(getUrl());
        builder.append(',');
        T body = getBody();
        HttpHeaders headers = getHeaders();
        if (body != null) {
            builder.append(body);
            if (headers != null) {
                builder.append(',');
            }
        }
        if (headers != null) {
            builder.append(headers);
        }
        builder.append('>');
        return builder.toString();
    }

    // Static builder methods

    /**
     * Create a builder with the given method and url.
     * 
     * @param method
     *            the HTTP method (GET, POST, etc)
     * @param url
     *            the URL
     * @return the created builder
     */
    public static BodyBuilder method(HttpMethod method, URI url) {
        return new DefaultBodyBuilder(method, url);
    }

    /**
     * Create an HTTP GET builder with the given url.
     * 
     * @param url
     *            the URL
     * @return the created builder
     */
    public static HeadersBuilder<?> get(URI url) {
        return method(HttpMethod.GET, url);
    }

    /**
     * Create an HTTP HEAD builder with the given url.
     * 
     * @param url
     *            the URL
     * @return the created builder
     */
    public static HeadersBuilder<?> head(URI url) {
        return method(HttpMethod.HEAD, url);
    }

    /**
     * Create an HTTP POST builder with the given url.
     * 
     * @param url
     *            the URL
     * @return the created builder
     */
    public static BodyBuilder post(URI url) {
        return method(HttpMethod.POST, url);
    }

    /**
     * Create an HTTP PUT builder with the given url.
     * 
     * @param url
     *            the URL
     * @return the created builder
     */
    public static BodyBuilder put(URI url) {
        return method(HttpMethod.PUT, url);
    }

    /**
     * Create an HTTP PATCH builder with the given url.
     * 
     * @param url
     *            the URL
     * @return the created builder
     */
    public static BodyBuilder patch(URI url) {
        return method(HttpMethod.PATCH, url);
    }

    /**
     * Create an HTTP DELETE builder with the given url.
     * 
     * @param url
     *            the URL
     * @return the created builder
     */
    public static HeadersBuilder<?> delete(URI url) {
        return method(HttpMethod.DELETE, url);
    }

    /**
     * Creates an HTTP OPTIONS builder with the given url.
     * 
     * @param url
     *            the URL
     * @return the created builder
     */
    public static HeadersBuilder<?> options(URI url) {
        return method(HttpMethod.OPTIONS, url);
    }

    /**
     * Defines a builder that adds headers to the request entity.
     * 
     * @param <B>
     *            the builder subclass
     */
    public interface HeadersBuilder<B extends HeadersBuilder<B>> {

        /**
         * Add the given, single header value under the given name.
         * 
         * @param headerName
         *            the header name
         * @param headerValues
         *            the header value(s)
         * @return this builder
         * @see HttpHeaders#add(String, String)
         */
        B header(String headerName, String... headerValues);

        /**
         * Set the list of acceptable {@linkplain HttpMediaType media types}, as
         * specified by the {@code Accept} header.
         * 
         * @param acceptableMediaTypes
         *            the acceptable media types
         */
        B accept(HttpMediaType... acceptableMediaTypes);

        /**
         * Set the list of acceptable {@linkplain Charset charsets}, as
         * specified by the {@code Accept-Charset} header.
         * 
         * @param acceptableCharsets
         *            the acceptable charsets
         */
        B acceptCharset(Charset... acceptableCharsets);

        /**
         * Set the value of the {@code If-Modified-Since} header.
         * <p>
         * The date should be specified as the number of milliseconds since
         * January 1, 1970 GMT.
         * 
         * @param ifModifiedSince
         *            the new value of the header
         */
        B ifModifiedSince(long ifModifiedSince);

        /**
         * Set the values of the {@code If-None-Match} header.
         * 
         * @param ifNoneMatches
         *            the new value of the header
         */
        B ifNoneMatch(String... ifNoneMatches);

        /**
         * Builds the request entity with no body.
         * 
         * @return the request entity
         * @see BodyBuilder#body(Object)
         */
        HttpRequestEntity<Void> build();
    }

    /**
     * Defines a builder that adds a body to the response entity.
     */
    public interface BodyBuilder extends HeadersBuilder<BodyBuilder> {

        /**
         * Set the length of the body in bytes, as specified by the
         * {@code Content-Length} header.
         * 
         * @param contentLength
         *            the content length
         * @return this builder
         * @see HttpHeaders#setContentLength(long)
         */
        BodyBuilder contentLength(long contentLength);

        /**
         * Set the {@linkplain HttpMediaType media type} of the body, as
         * specified by the {@code Content-Type} header.
         * 
         * @param contentType
         *            the content type
         * @return this builder
         * @see HttpHeaders#setContentType(HttpMediaType)
         */
        BodyBuilder contentType(HttpMediaType contentType);

        /**
         * Set the body of the request entity and build the RequestEntity.
         * 
         * @param <T>
         *            the type of the body
         * @param body
         *            the body of the request entity
         * @return the built request entity
         */
        <T> HttpRequestEntity<T> body(T body);

        /**
         * Set the body and type of the request entity and build the
         * RequestEntity.
         * 
         * @param <T>
         *            the type of the body
         * @param body
         *            the body of the request entity
         * @param type
         *            the type of the body, useful for generic type resolution
         * @return the built request entity
         * @since 4.3
         */
        <T> HttpRequestEntity<T> body(T body, Type type);
    }

    private static class DefaultBodyBuilder implements BodyBuilder {

        private final HttpMethod method;

        private final URI url;

        private final HttpHeaders headers = new HttpHeaders();

        public DefaultBodyBuilder(HttpMethod method, URI url) {
            this.method = method;
            this.url = url;
        }

        @Override
        public BodyBuilder header(String headerName, String... headerValues) {
            for (String headerValue : headerValues) {
                this.headers.add(headerName, headerValue);
            }
            return this;
        }

        @Override
        public BodyBuilder accept(HttpMediaType... acceptableMediaTypes) {
            this.headers.setAccept(Arrays.asList(acceptableMediaTypes));
            return this;
        }

        @Override
        public BodyBuilder acceptCharset(Charset... acceptableCharsets) {
            this.headers.setAcceptCharset(Arrays.asList(acceptableCharsets));
            return this;
        }

        @Override
        public BodyBuilder contentLength(long contentLength) {
            this.headers.setContentLength(contentLength);
            return this;
        }

        @Override
        public BodyBuilder contentType(HttpMediaType contentType) {
            this.headers.setContentType(contentType);
            return this;
        }

        @Override
        public BodyBuilder ifModifiedSince(long ifModifiedSince) {
            this.headers.setIfModifiedSince(ifModifiedSince);
            return this;
        }

        @Override
        public BodyBuilder ifNoneMatch(String... ifNoneMatches) {
            this.headers.setIfNoneMatch(Arrays.asList(ifNoneMatches));
            return this;
        }

        @Override
        public HttpRequestEntity<Void> build() {
            return new HttpRequestEntity<Void>(this.headers, this.method, this.url);
        }

        @Override
        public <T> HttpRequestEntity<T> body(T body) {
            return new HttpRequestEntity<T>(body, this.headers, this.method, this.url);
        }

        @Override
        public <T> HttpRequestEntity<T> body(T body, Type type) {
            return new HttpRequestEntity<T>(body, this.headers, this.method, this.url, type);
        }
    }

}